Corexit lowers oxygenation levels and increases cloudiness in water because of dispersed oil, creating a poor environment for marine life
Journal Article
Berninger, J. P., Williams, E., & Brooks, B. W. (2011). An initial probabilistic hazard assessment of oil dispersants approved by the united states national contingency plan. Environmental Toxicology & Chemistry, 30(7), 1704-1708. doi:10.1002/etc.532
Lab Procedure- Source
This link is a lab that some students have done which recreates the conditions of the oil spill which we will try to copy in order to compare Dawn and Corexit http://web.ebscohost.com/ehost/pdfviewer/pdfviewer?sid=c3941635-3e23-4cd5-b8e1-e3ff34d2cc51%40sessionmgr113&vid=5&hid=119 We will compare the effect of Dawn dish soap and Corexit in the dispersion of oil. Also, we will investigate the detrimental effects of Corexit in the environment because it only disperses oil, it does not get rid of it.
Apparatus and Chemicals Needed
Corexit
Dawn dish soap
Digital titrator
Magnetic stirrer
Vegetable oil
Safety Information
Typical lab safety, nothing extreme
Other Information
connects to the Deep Horizons oil spill in the Gulf of Mexico- animal life decreases
Final Report
Abstract A STUDY OF THE EFFECTS OF THE OIL DISPERSANT COREXIT ON WATER QUALITY. Mara Walli and Claire Flom-Staab. This lab investigated the use of the oil dispersant Corexit, and its effects on water quality. Corexit was used to help clean up the oil spill in the Gulf of Mexico, and it successfully broke apart the oil. However, the effects on the water beneath the surface are in question. Both dissolved oxygen level and cloudiness were tested in the lab as measures of water quality, for these are two factors that determine the habitability of water. Much aquatic life requires at least 5.0 mg/L dissolved oxygen to survive, and unnaturally cloudy water due to pollutants can absorb more solar radiation, decreasing visibility and sunlight for the marine life. The oxygen levels, measured with a titration kit, started at a healthy 8.8 mg/L for saltwater, but decreased to 5.3 mg/L after oil and Corexit were added. Since these results suggest lower water qualities but do not determine whether the lower quality is due to the oil itself or the Corexit dispersant, further research was done to isolate the effect of oil and the effect of oil and Corexit. In this trial, the oxygen levels decreased equal amounts, to 3.3 and 3.2 mg/L, over a 72-hour period. Therefore, the oil itself was likely the main factor that affected the dissolved oxygen level, not the Corexit. Cloudiness was measured in terms of transmittance and absorption of light through the liquid using a spectrophotometer. The saltwater was clear, with 100% transmittance and .000 absorption. The water with Corexit was very cloudy, with 55.5% transmittance and .256 absorption after the Corexit had been in the solution for over 24 hours. The study suggests that only the oil caused the decrease in dissolved oxygen level, potentially to dangerously low levels, and only the Corexit caused the increased cloudiness. Therefore, further research on the negative effects of cloudiness in terms of temperature and pH would shed more light on the negative effects of Corexit. Keywords: Corexit, dissolved oxygen level, spectrophotometer, transmittance, absorption.
Lab Apparatus
This titration is part of the process in finding the amount of oxygen in a particular solution.
This machine uses light to measure different properties of a solution such as transmittance and absorption.
Figure 1: Titration for dissolved oxygen level Figure 2: Spectrophotometer
Denny, M. W., Gaines, S. D., Cummings, M., & Johnsen, S. (2007). Lights, Effects of. Encyclopedia of Tidepools and Rocky Shores (pp. 327-330). Berkeley: University of California Press. Retrieved May 22, 2012, from http://www.biology.duke.edu/johnsenlab/pdfs/pubs/intertidal.pdf
NOAA - No Dead Zones Observed or Expected as Part of BP Deepwater Horizon Oil Spill. (2010, November 7). NOAA - National Oceanic and Atmospheric Administration. Retrieved May 16, 2012, from http://www.noaanews.noaa.gov/stories2010/20100907_jag3.html
by Claire and Mara
http://web.ebscohost.com/ehost/pdfviewer/pdfviewer?sid=c3941635-3e23-4cd5-b8e1-e3ff34d2cc51%40sessionmgr113&vid=5&hid=119
We will compare the effect of Dawn dish soap and Corexit in the dispersion of oil. Also, we will investigate the detrimental effects of Corexit in the environment because it only disperses oil, it does not get rid of it.
Final Report
Abstract
A STUDY OF THE EFFECTS OF THE OIL DISPERSANT COREXIT ON WATER QUALITY. Mara Walli and Claire Flom-Staab. This lab investigated the use of the oil dispersant Corexit, and its effects on water quality. Corexit was used to help clean up the oil spill in the Gulf of Mexico, and it successfully broke apart the oil. However, the effects on the water beneath the surface are in question. Both dissolved oxygen level and cloudiness were tested in the lab as measures of water quality, for these are two factors that determine the habitability of water. Much aquatic life requires at least 5.0 mg/L dissolved oxygen to survive, and unnaturally cloudy water due to pollutants can absorb more solar radiation, decreasing visibility and sunlight for the marine life. The oxygen levels, measured with a titration kit, started at a healthy 8.8 mg/L for saltwater, but decreased to 5.3 mg/L after oil and Corexit were added. Since these results suggest lower water qualities but do not determine whether the lower quality is due to the oil itself or the Corexit dispersant, further research was done to isolate the effect of oil and the effect of oil and Corexit. In this trial, the oxygen levels decreased equal amounts, to 3.3 and 3.2 mg/L, over a 72-hour period. Therefore, the oil itself was likely the main factor that affected the dissolved oxygen level, not the Corexit. Cloudiness was measured in terms of transmittance and absorption of light through the liquid using a spectrophotometer. The saltwater was clear, with 100% transmittance and .000 absorption. The water with Corexit was very cloudy, with 55.5% transmittance and .256 absorption after the Corexit had been in the solution for over 24 hours. The study suggests that only the oil caused the decrease in dissolved oxygen level, potentially to dangerously low levels, and only the Corexit caused the increased cloudiness. Therefore, further research on the negative effects of cloudiness in terms of temperature and pH would shed more light on the negative effects of Corexit.
Keywords: Corexit, dissolved oxygen level, spectrophotometer, transmittance, absorption.
Lab Apparatus
Figure 1: Titration for dissolved oxygen level Figure 2: Spectrophotometer
Summary Graphics
Citations
COREXIT® Technology. (n.d.) Nalco: An Ecolab Company. Retrieved February 12, 2012, from
http://www.nalco.com/applications/corexit-technology.htm
Denny, M. W., Gaines, S. D., Cummings, M., & Johnsen, S. (2007). Lights, Effects of. Encyclopedia of Tidepools and Rocky Shores (pp. 327-330). Berkeley: University of California Press. Retrieved May 22, 2012, from http://www.biology.duke.edu/johnsenlab/pdfs/pubs/intertidal.pdf
Dissolved Oxygen and Water Quality . (n.d.). Commonwealth of Kentucky. Retrieved February 7,
2012, from http://www.state.ky.us/nrepc/water/wcpdo.htm
Mulkins-Phillips, G. J., & Steware, J. (1974). Effect of Four Dispersants on Biodegradation and Growth of Bacteria on Crude Oil. American Society for Microbiology, 28(4), 547-552. Retrieved May 16, 2012, from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC186769/pdf/applmicro00016-0045.pdfNOAA - No Dead Zones Observed or Expected as Part of BP Deepwater Horizon Oil Spill. (2010, November 7). NOAA - National Oceanic and Atmospheric Administration. Retrieved May 16, 2012, from http://www.noaanews.noaa.gov/stories2010/20100907_jag3.html
Oil Dispersion and How it Works [Video file]. Retrieved from http://www.nalco.com/applications/corexit-technology.htm
Schmidt, C.W. (2010). Between the devil and the deep blue sea. Environmental Health Perspectives, 142, A338-A344.
Spectrophotometer Laboratory Manual. (1996). Batavia: Flinn Scientific, Inc..
Stewart, P., Tedaldi, D., Lewis, A., & Goldman, E. (1993). Biodegradation Rates of Crude Oil in Seawater. Water Environment Research,, 65(7), 845-848. Retrieved May 16, 2012, from http://www.jstor.org/stable/pdfplus/25044389.pdf?acceptTC=true
The Effects Of Chemical Dispersants On Marine Life And The Environment | Eco Green Projects. (2010, June 13). Eco Green Projects- Live Green, Live Friendly. Retrieved May 16, 2012, from http://www.ecogreenprojects.com/2010/06/what-are-the-effects-of-chemical-dispersants-on-marine-life-and-the-environment/
Water Pollution. (n.d.). Safe Drinking Water Foundation. Retrieved Feb. 13, 2012.http://www.safewater.org/PDFS/resourcesknowthefacts/WaterPollution.pdf
Audio File